Abstract : The paper is concerned with the continuous conflict, which occasionally poses a specific problem of decision, between the legitimate ends of security in military technology and of disclosure for the sake of demonstration potential. The needs of security may conflict with many other desirable ends as well (e.g., accelerating the rate of scientific progress), but such considerations are ruled out of the present discussion except in so far as they may be supplementary to the considerations governing the decision to disclose for the sake of demonstration value, or to refrain from so doing.